Copyright protection exists from the moment an original, creative, work is fixed, e.g. recorded, written down, saved, etc. Copyright gives to the author/creator exlusive rights to copy, distribute, make derivatives, perform and display a work. No registration or © symbol is needed and protection lasts the life of the author plus 70 years.
There are different ways that you can use material without infringing on the author/creator rights.
Are you starting a 3D imaging or printing project?